A scaled thermal-diffusivity-based frequency reference in 0.16μm CMOS

Abstract

A 16MHz frequency reference that exploits the well-defined thermal diffusivity of IC-grade silicon is presented. The reference is realized in a 0.16μm baseline CMOS process. Occupying 0.5mm², its absolute inaccuracy after a room temperature trim is ±0.1% from −55°C to 125°C (24 samples). Its cycle-to-cycle jitter is less than 45ps (rms), and it dissipates 2.1mW from a 1.8V supply. Compared to a previous design in a 0.7μm CMOS process, this work achieves 10× higher frequency, 7× less jitter, 3.7× less power, and 12× less chip area, while maintaining the same accuracy. This demonstrates that thermal-diffusivity-based frequency references benefit strongly from technology scaling.